2000
#8,421
National surname rank
Recorded bearers 3,605
First available Census row
Per 100,000 1.34
Rare Last name
Dunphy
An Irish surname derived from the Gaelic "Donnchadha," meaning "brown warrior" or "brown-haired warrior."
According to the 2020 US Census Bureau surname tables, roughly 4,181 Americans carry the last name Dunphy. That puts it at #8,641 in the national surname ranking, appearing at a frequency of 1.22 per 100,000 people (about 1 in 81,979 residents).
This page is the full Name Census profile for the Dunphy surname. You will find the Census Bureau frequency data, a multi-census history view, an ancestry and ethnicity breakdown based on self-reported demographics, the name's meaning and origin where available, and answers to the most common questions people ask about this surname.
For British records, Name Census UK has a British surname profile for Dunphy with 1881 census detail, origin facts and modern UK distribution where available.
Bearers in the US
4.2K
1 in 81,979
Census rank
#8,641
2020 decennial data
Per 100,000
1.2
Frequency rate
Recorded bearers
3.6K
rare in the US
Popularity narrative
The Census Bureau recorded 3,646 bearers of the surname Dunphy in its 2020 decennial surname file. At a rate of 1.22 per 100,000 residents, it holds the 8641st position in the national surname ranking.
Among Census respondents with the surname Dunphy, the largest self-reported group is White at 90.9%. The next largest groups are Hispanic (4.1%) and Two or More Races (3.5%).
Origin
Meaning and origin of Dunphy
The surname Dunphy is an anglicized version of the Irish Gaelic Ó Donnchadha, which means "descendant of Donnchadh". Donnchadh was a popular personal name derived from the Gaelic elements "donn" meaning brown, and "cath" meaning battle or warrior. The name originated in County Kerry, Ireland, in the medieval period.
The earliest recorded instance of the name Dunphy can be traced back to the Annals of the Four Masters, a chronicle of medieval Irish history compiled in the 17th century. It mentions Donnchadh Ó Donnchadha, who was a prominent chieftain in Kerry in the 14th century.
In the 16th century, the surname appeared in the Fiants of the Tudor Sovereigns, a collection of documents from the English government in Ireland. One notable figure was Edmond Dunphy, who was granted lands in County Kerry in 1586.
During the Cromwellian conquest of Ireland in the 17th century, many Dunphys were displaced from their ancestral lands. Some migrated to other parts of Ireland, while others emigrated to Europe and the Americas.
One of the earliest recorded instances of the name in America was John Dunphy, who arrived in Virginia in 1635. Another notable figure was Thomas Dunphy, born in 1664 in County Kerry, who later settled in Maryland and became a prominent landowner.
In the 18th century, the surname appeared in various records across Ireland, such as the Census of Elphin and the Diocesan Returns. Prominent individuals included Reverend James Dunphy, a Catholic priest from County Kerry, and John Dunphy, a member of the Irish Parliament in the late 1700s.
Other notable individuals with the surname Dunphy throughout history include:
1. Alice Dunphy-Schwartz (1905-1985), American politician and lawyer from New York.
2. Michael Dunphy (1915-2000), Irish writer and journalist known for his works on Irish history and culture.
3. Sean Dunphy (1919-2011), Irish hurler who played for the Waterford senior team in the 1940s.
4. Graeme Dunphy (born 1962), New Zealand rugby union player and coach.
5. Shane Dunphy (born 1981), Irish Gaelic footballer who played for the Waterford senior team.
Demographics
Ancestry and ethnicity for Dunphy
Among Census respondents with the surname Dunphy, the largest self-reported group is White at 90.9%. The next largest groups are Hispanic (4.1%) and Two or More Races (3.5%).
The bar chart below shows how Dunphy bearers described their own race and ethnicity on the 2020 Census form. The Census Bureau groups responses into six broad categories: White, Black or African American, Hispanic or Latino, Asian and Pacific Islander, American Indian and Alaska Native, and Two or More Races. When a category has too few respondents for a given surname, the Bureau suppresses the figure to protect individual privacy, which is why some names show fewer than six slices.
Percentages are shown for every Census year so the breakdown stays comparable over time. When the source file also includes raw headcounts, Name Census shows those alongside the percentages in the legend.
Keep in mind that these are self-reported numbers. A person's surname does not determine their race or ethnicity, and the distribution you see here reflects the specific population who happened to carry the Dunphy surname at the time of the 2020 Census, not any inherent property of the name itself.
- White90.9% · 3,313
- Hispanic or Latino4.1% · 149
- Two or more races3.5% · 126
- Asian and Pacific Islander0.9% · 33
- Black or African American0.5% · 17
- American Indian and Alaska Native0.2% · 8
Timeline
Historical Census data for Dunphy
Dunphy appears in 3 published Census surname files: 2000, 2010, 2020. The cards below show how the name's rank and bearer count changed across each release.
2010
#8,928
National surname rank
Recorded bearers 3,666
+61 bearers (+1.7%)
Per 100,000 1.24
Rank movement Down 507 places
2020
#8,641
National surname rank
Recorded bearers 3,646
-20 bearers (-0.5%)
Per 100,000 1.22
Rank movement Up 287 places
| Year | Rank | Count | Per 100K | Count change | Rank change |
|---|---|---|---|---|---|
| 2000 | #8,421 | 3,605 | 1.34 | First available Census row | First available Census row |
| 2010 | #8,928 | 3,666 | 1.24 | +61 bearers (+1.7%) | Down 507 places |
| 2020 | #8,641 | 3,646 | 1.22 | -20 bearers (-0.5%) | Up 287 places |
For 2020, the Census Bureau published race and Hispanic-origin columns as counts rather than percentages. Name Census converts those counts back into shares so the ancestry section stays comparable with the older surname files.
Year on year
2010 vs 2020 Census
How has the Dunphy surname changed between Census years? The chart shows bearer count side by side, and the table compares rank, count, and frequency.
Census year comparison
20102020
| Metric | 2010 | 2020 | Change |
|---|---|---|---|
| Rank | #8,928 | #8,641 | 3.2% |
| Count | 3,666 | 3,646 | -0.5% |
| Per 100K | 1.24 | 1.22 | -1.6% |
Between the 2010 and 2020 Census, the number of Dunphy bearers went from 3,666 to 3,646 (-0.5% change). The surname moved up 287 positions in the national ranking, going from #8,928 to #8,641.
FAQ
Dunphy surname: questions and answers
How many people in the U.S. have the surname Dunphy?
Name Census estimates that about 4,181 living Americans carry the surname Dunphy. Using the current population baseline, that works out to roughly 1 in 81,979 residents.
How common is Dunphy?
Dunphy ranks #8,641 in the 2020 Census surname tables and is classified on this site as "Rare." The Census recorded the name at a frequency of 1.22 per 100,000 residents, which is about 1 people out of every 100,000.
How many people with this surname were counted in the Census?
The raw 2020 Census file counted 3,646 people with the surname Dunphy. That is different from the site's living-bearer estimate (4,181), which projects the surname's present-day count by applying the Census frequency rate to the current U.S. population.
What does 1.22 per 100,000 actually mean?
It is the Census Bureau's normalized frequency measure. A rate of 1.22 per 100,000 means that if you picked a random group of 100,000 U.S. residents, you would expect about 1 of them to have the surname Dunphy.
Has Dunphy become more or less common over time?
Between 2010 and 2020, the surname Dunphy went from 3,666 recorded bearers to 3,646. That is a decrease of 20 (-0.5%). In the national ranking it rose from #8,928 to #8,641.
What does the Census say about the background of Dunphy?
Among Census respondents with the surname Dunphy, the largest self-reported group is White at 90.9%. The next largest groups are Hispanic (4.1%) and Two or More Races (3.5%). These figures come from the 2020 Census Bureau surname tables, based on how respondents described their own race and ethnicity.
Which group reports this surname most often?
White is the largest self-reported group for the surname Dunphy in the 2020 Census, accounting for 90.9% (3,313 people in the source table).
What is the full ancestry breakdown?
Dunphy appears across multiple self-reported groups in the Census data. The largest shares in the 2020 file are White (90.9%), Hispanic (4.1%), Two or More Races (3.5%). For 2020, the source file also published raw headcounts for each group, which is why this page can show both percentages and counts in the ancestry section.
Is this page using the latest Census data?
Yes. This page is using the latest surname file currently loaded on Name Census, which is 2020. The historical section above also keeps any older Census surname entries we have for Dunphy (2000, 2010, 2020).
Does the Census include every surname?
No. The Census Bureau only publishes surnames that appeared at least 100 times in a given decennial Census. That means very rare surnames are excluded entirely, and a surname can appear in one Census release but disappear from a later one if it falls below the reporting threshold.
Why don't the ancestry percentages always add up to exactly 100%?
There are two main reasons: rounding and suppression. The Census Bureau rounds published values, and it may suppress very small cells to protect privacy. For 2020, the Bureau also published raw group counts rather than direct percentages, so Name Census converts those counts back into shares for comparability across census years.
What does Dunphy mean?
An Irish surname derived from the Gaelic "Donnchadha," meaning "brown warrior" or "brown-haired warrior." The fuller origin note on this page goes into more detail.
Where does the surname data come from?
All surname statistics on Name Census are drawn from the US Census Bureau's decennial surname frequency tables. These files list every surname that appeared 100 or more times in the 2020 Census, along with a count, a per-100,000 rate, and a self-reported demographic breakdown. You can read the full explanation on our methodology page.
How does Name Census estimate living bearers?
For surnames, Name Census does not age cohorts the way it does for first names. Instead, it takes the Census Bureau's published frequency for Dunphy (1.22 per 100,000) and applies that rate to the current U.S. resident population to estimate how many living Americans have the surname today.
How many people have the surname Dunphy?
HowManyOfMe.org, our sister site, answers that with the living-bearer count in one glance.